Final answer:
Graded Response is the concept being described in this question. It refers to the idea that the effect of a chemical or substance on an individual is dose-dependent.
Step-by-step explanation:
The concept being described in this question is Graded Response. Graded response refers to the idea that the effect of a chemical or substance on an individual is dose-dependent. It means that there is a minimum concentration (threshold) at which no effect is produced, a concentration that can cause death (lethal concentration), and a range of concentrations in between that will give varying levels of graded effects.